How to simulate cobalt/nickel solvent extraction (d2ehpa)
A laterite leach liquor (Co/Ni/Mg in dilute sulfate solution) meets a D2EHPA-in-kerosene organic phase across a 20-stage countercurrent extraction circuit run at pH 5.2 — the real industrial operating window (e.g. Bulong, Murrin Murrin, Western Australia) that exploits the ~1 pH-unit gap between Co and Ni's D2EHPA extraction isotherms: Co extracts into the organic while Ni (and Mg gangue) are rejected to the raffinate. The loaded organic then meets fresh dilute-acid strip liquor across a 10-stage strip circuit at pH 1.0 (well below Co's isotherm), reversing the equilibrium to recover a concentrated cobalt strip liquor and regenerate barren organic. Real pH-isotherm chemistry throughout, not a fitted shortcut K_D.
- 1Open the ready-made model
Open the "Cobalt/nickel solvent extraction (D2EHPA)" model in the MaximaLabs workspace — no install, no license. It loads live on the canvas, ready to edit and run.
- 2Confirm the thermodynamics
This process is modeled with the BRINE property package over water, co, ni, mg, kerosene — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains 2× Strip Stage. Every block is a real, solvable unit op you can reconfigure on the canvas.
- 4Run the simulation
Click Run. The deterministic solver converges the material and energy balances (recycles included) and fills the live stream table — the AI never invents a number.
- 5Read the results and iterate
Inspect the converged streams, tweak a spec, and re-run — or ask the AI copilot to explain a result or diagnose a failed solve in plain English.
- Thermodynamics
- BRINE
- Components
- water, co, ni, mg, kerosene
- Unit operations
- 2× Strip Stage
Opens live on the canvas — free, no install.
Explore the model & flowsheetModeling assumptions & limitations
What this model captures, and what it deliberately does not — from the engineers who built it.
- 1The regenerated organic and strip liquor aren't recycled back upstream (an open-loop v1, same posture as this session's other new cycle examples) — a real plant recycles both; strip_stage's distribution_coefficients is the numeric inverse of the same isotherm (1/D_Co at pH 1.0 = 1e8, i.e. strongly favors the aqueous phase) since the ph= mode always assumes the aqueous-feed/organic-solvent extraction direction, not reverse stripping.
Frequently asked questions
- What does the Cobalt/nickel solvent extraction (D2EHPA) model simulate?
- A laterite leach liquor (Co/Ni/Mg in dilute sulfate solution) meets a D2EHPA-in-kerosene organic phase across a 20-stage countercurrent extraction circuit run at pH 5.2 — the real industrial operating window (e.g. Bulong, Murrin Murrin, Western Australia) that exploits the ~1 pH-unit gap between Co and Ni's D2EHPA extraction isotherms: Co extracts into the organic while Ni (and Mg gangue) are rejected to the raffinate. The loaded organic then meets fresh dilute-acid strip liquor across a 10-stage strip circuit at pH 1.0 (well below Co's isotherm), reversing the equilibrium to recover a concentrated cobalt strip liquor and regenerate barren organic. Real pH-isotherm chemistry throughout, not a fitted shortcut K_D.
- Which thermodynamic method does it use?
- The BRINE property package, over water, co, ni, mg, kerosene — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains 2× Strip Stage. Every block is a real, solvable unit operation you can reconfigure, add to, or remove.
- Do I need to install software or buy a license?
- No. Cobalt/nickel solvent extraction (D2EHPA) runs entirely in your browser on MaximaLabs — free, no install, no license. Open the model to load it live and run the deterministic solver.
More guides like this
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Direct lithium extraction + LiOH crystallization
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Acid-mine-drainage neutralization: staged lime precipitation
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Crystallization with agglomeration (distributed CSD)
An MSMPR crystallizer solved with the rigorous distributed population balance (not just moments): the full crystal-size distribution is computed on a size grid, and an agglomeration (aggregation) kernel combines fine crystals into larger ones — coarsening the mass-weighted mean size (d43) and broadening the distribution (CV rises above the growth-only MSMPR value of ~1.0) while conserving mass exactly. The distribution, its coefficient of variation, and d43 propagate on the solid stream into the filter and dryer — the gPROMS/gCRYSTAL capability the moment model structurally cannot provide.